Wireless radio frequency or microwave communications are used in an increasing number of applications. In addition to current and well-known applications such as mobile phones, wireless communications systems are foreseen to connect practically all items used in homes and offices. Applications such as wireless local area networks (WLAN) and Bluetooth™ are widely used, as well as radio frequency or microwave transmission links across large distances. One of the challenges in such applications is mitigating the fading of the wireless transmission signal due to multipath propagation caused by obstructions and disturbances in the transmission environment. Multipath propagation can be reduced by using antennas with tightly focused beams, signal processing, or special modulation schemes. While high-gain antennas with focused beams are useful for fixed point-to-point communications, mobile and general-purpose communication applications require antennas with wide beams or capabilities for smart beam steering. However, smart beam-steering antennas are usually complex as they require controlling electronics and computational power.
All of the conventional methods described above are employed to reduce the effects of multipath propagation but impose added costs or tradeoffs in the performance or usability of the system. It would be desirable to provide a solution that could enhance communications in severe multipath environments without imposing added costs or losses in performance.